The objective of the proposed research is to develop and pilot test a questionnaire to measure the occurrence of lymphedema in breast cancer patients. Lymphedema or arm edema has been identified by women experiencing it as one of the most distressing long-term consequences of breast cancer treatment. Yet, to date, there have been no population- based studies of the incidence of lymphedema, risk factors for its occurrence and its impact on the quality of life of breast cancer patients. As clinical trials continue to document equivalent mortality rates for a variety of treatment options for breast cancer, there is a growing need to understand whether there are differences between treatments in long-term morbidity. To make population-based studies of lymphedema feasible, a questionnaire is needed that accurately assesses the presence of lymphedema and is easily administered to large numbers of women. The specific aims of this study represent a series of standard approaches, employing a mix of qualitative and quantitative methods, tha will be used to develop the lymphedema questionnaire. They are: 1) identify relevant aspects of lymphedema to be measured, through literature review, consultation with experts, and conducting focus group with breast cancer patients currently being treated for lymphedema; 2) construct a questionnaire to be administered by telephone, 3) assess face and content validity of the developed questionnaire through review by a panel of experts and patients with lymphedema; 4) pilot test the questionnaire on 50 breast cancer patients clinically assessed to have mild, moderate, severe or no lymphedema; 5) assess concurrent validity through comparison of the questionnaire results on these 50 patients to clinical judgment of the presence and degree of lymphedema and to circumferential and volumetric measures of both arms; and 6) revise the questionnaire based on the results of the pilot test and re-assess its validity using an additional 25 patients. Patients for the focus groups will be recruited from the Breast Cancer Physical Center in Philadelphia. There will be two groups of 8-10 patients in each. Breast cancer patients for the pilot study will be recruited through physicians at the Hospital of the University of Pennsylvania and through the Breast Cancer Physical Therapy Center.